One mode of insulin infusion treatment for diabetes includes infusion pump therapy via a catheter, needle or other type of cannula. Infusion pumps offer the advantages of continuous infusion of insulin, precision dosing, and programmable delivery schedules. Together, these advantages result in more accurate blood glucose control. In this mode of insulin infusion treatment, the infusion pump remains attached to the user and required doses of insulin are delivered to the user via the pump.
One type of cannula is a catheter, which generally is a tube that can be inserted into the body to permit the administration of fluids. In infusion pump therapy, the types and sizes of the catheter may vary, but generally, the catheter is a thin, flexible tube. In some uses, however, it may be larger and/or rigid.
One type of conventional infusion set is sold as the Quick-Set® infusion set by Medtronic. In such devices, the infusion pump includes a catheter assembly connected to a pump via a tubing set, and a separate insertion device inserts and/or attaches the catheter assembly into to a user via an introducer needle provided as part of the infusion set. The infusion set and insertion device can also be combined, as in the Mio® infusion set sold by Medtronic, which is an “all-in-one” design that combines the infusion set and insertion device into one unit.
A conventional infusion device can include a fluid connector hub, which may be releasably attached to a base that can be secured to a user's skin. An infusion pump supplies fluid to a catheter via the fluid connector hub/base engagement.
With conventional infusion devices, however, there are concerns that, after insertion of the catheter and removal of the insertion device, the introducer needle is exposed and may cause physical damage from a needle stick. There are also concerns over the difficulty of balancing the force required to disconnect the tubing without pulling the catheter from the user's skin versus having enough retention force to secure the infusion components for everyday infusion. Another concern is that there may be a need to design a rotational lock between the fluid connector hub and the base post. Yet another concern is that the separation force needs to be designed such that if a user accidentally snags the extension tubing on an external structure (e.g., a doorknob), the extension tubing will disconnect from the fluid connector hub without removing the catheter from the user's skin, thus saving the patient from the need to obtain, re-insert, and connect a new infusion set.